package com.wch.spring.factory;

import com.wch.spring.annotation.MyAutowired;
import com.wch.spring.annotation.MyService;
import com.wch.spring.dao.AccountDao;
import com.wch.spring.utils.TransactionManager;
import net.sf.cglib.proxy.Enhancer;
import net.sf.cglib.proxy.MethodInterceptor;
import net.sf.cglib.proxy.MethodProxy;

import java.lang.reflect.InvocationHandler;
import java.lang.reflect.Method;
import java.lang.reflect.Proxy;

/**
 *
 * 代理对象工厂：生成代理对象
 */


@MyService("proxyFactory")
public class ProxyFactory {

    @MyAutowired
    private TransactionManager transactionManager;

    public void setTransactionManager(TransactionManager transactionManager) {
        this.transactionManager = transactionManager;
    }

    /**
     * Jdk动态代理
     * @param obj  委托对象
     * @return   代理对象
     */
    public Object getJdkProxy(Object obj) {

        // 获取代理对象
        return  Proxy.newProxyInstance(obj.getClass().getClassLoader(), obj.getClass().getInterfaces(), (proxy, method, args) -> {
            Object result = null;
            try{
                // 开启事务(关闭事务的自动提交)
                transactionManager.beginTransaction();

                result = method.invoke(obj,args);

                // 提交事务
                transactionManager.commit();
            }catch (Exception e) {
                e.printStackTrace();
                // 回滚事务
                transactionManager.rollback();
                // 抛出异常便于上层servlet捕获
                throw e;
            }
            return result;
        });

    }


    /**
     * 使用cglib动态代理生成代理对象
     * @param obj 委托对象
     * @return
     */
    public Object getCglibProxy(Object obj) {
        return  Enhancer.create(obj.getClass(), (MethodInterceptor) (o, method, objects, methodProxy) -> {
            Object result = null;
            try{
                // 开启事务(关闭事务的自动提交)
                transactionManager.beginTransaction();

                result = method.invoke(obj,objects);

                // 提交事务

                transactionManager.commit();
            }catch (Exception e) {
                e.printStackTrace();
                // 回滚事务
                transactionManager.rollback();

                // 抛出异常便于上层servlet捕获
                throw e;

            }
            return result;
        });
    }
}
